Yet Another Reason Not to Snack at Night

Eating when we should be sleeping could disrupt our skin’s ability to protect itself from the sun’s harmful rays, researchers now say. Specifically, per a ScienceDaily news release, noshing down late at night can mess with the skin’s biological clock, which in turn can affect the effectiveness during daylight hours of a particular enzyme that shields the skin from the sun’s ultraviolet rays. Even Dr. Joseph S. Takahashi—the geneticist whose 1997 claim to fame was discovering the “clock gene” that regulates our mammalian circadian rhythms—was taken aback when he saw the results of his latest study, published in the journal Cell Reports. “This finding is surprising,” he says. “I did not think the skin was paying attention to when we are eating.”

Mice in this experiment who ate only during the day (i.e., not the nocturnal creatures’ normal feeding time) didn’t express as much of the skin gene XPA during the time they should have been resting. They also suffered worse skin damage when exposed to UVB rays than mice fed at night and who didn’t exhibit a shift in XPA cycles. The research follows on the heels of other research that shows, for instance, that drinking on the beach is bad, reports the Los Angeles Times. The researchers concede the study may not speak to how human skin genes react to food intake, or whether diurnal (daytime) creatures are susceptible to sleep-time snacking the way the nocturnal mice in the study were, reports Food52. “But it’s fascinating to me that the skin would be sensitive to the timing of food intake,” study co-author Bogi Andersen says, per the release.